Thomas Hobbes

“ If it were well observed, whether the image of the person in a dream be as obedient to the accidental heat of him that dreameth, as waking his heat is to the person, and if so, then is such motion reciprocal. Another sign that dreams are caused by the action of the inward parts, is the disorder and casual consequence of one conception or image to another: for when we are waking, the antecedent thought or conception introduceth, and is cause of the consequent, as the water followeth a man's finger upon a dry and level table. ”

“ There is yet another kind of. imagination, which for clearness contendeth with sense, as well as a dream; and that is, when the action of sense hath been long or vehement: and the experience thereof is more frequent in the sense of seeing, than the rest. An example whereof is, the image remaining before the eye after a steadfast looking upon the sun. Also, those little images that appear before the eyes in the dark (whereof I think every man hath experience, but they most of all, that are timorous or superstitious) are examples of the same. ”

“ As standing water put into motion by the stroke of a stone, or blast of wind, doth not presently give over moving as soon as the wind ceaseth, or the stone settleth: so neither doth the effect cease which the object hath wrought upon the brain, so soon as ever by turning aside of the organ the object ceaseth to work; that is to say, though the sense be past, the image or conception remaineth; but more obscurely while we are awake, because some object or other continually plieth and soliciteth our eyes, and ears, keeping the mind in a stronger motion, whereby the weaker doth not easily appear. ”

“ Old men being commonly less healthful and less free from inward pains, are thereby more subject to dreams, especially such dreams as be painful: as dreams of lust, or dreams of anger, according as the heart, or other parts within, work more or less upon the brain, by more or less heat. So also the descent of different sorts of phlegm maketh one to dream of different tastes of meats or drinks. And I believe there is a reciprocation of motion from the brain to the vital parts, and back from the vital parts to the brain; whereby not only imagination begetteth motion in those parts ”

“ From the same ground it proceedeth, that men wonder not in their dreams at places and persons, as they would do waking: for waking, a man would think it strange to be in a place wherein he never was before, and remember nothing of how he came there. But in a dream, there cometh little of that kind into consideration. The clearness of conception in a dream, taketh away distrust, unless the strangeness be excessive, as to think himself fallen from on high without hurt, and then most commonly he awaketh. ”

“ But in dreams there is commonly no coherence (and when there is, it is by chance) , which must proceed from this, that the brain in dreams is not restored to its motion in every part alike; whereby it cometh to pass, that our thoughts appear like the stars between the flying clouds, not in the order which a man would choose to observe them in, but as the uncertain flight of broken clouds permit. ”

“ Nor is it impossible for a man to be so far deceived, as when his dream is past, to think it real: for if he dream of such things as are ordinarily in his mind,. and in such order as he useth to do waking, and withal that he laid him down to sleep in the place where he findeth himself when he awaketh (all which may happen) I know no Kritirion or mark by which he can discern whether it were a dream or not, and do therefore the less wonder to hear a man sometimes to tell his dream for a truth, or to take it for a vision. ”

“ For example, a man that is present in a foreign city, seeth not only whole streets, but can also distinguish particular houses, and parts of houses; departed thence, he cannot distinguish them so particularly in his mind as he did, some house or turning escaping him ”

“ If this be true, and that sad imaginations nourish the spleen, then we see also a cause, why a strong spleen reciprocally causeth fearful dreams. And why the effects of lasciviousness may in a dream produce the image of some person that hath caused them. ”